It was one of those throwaway lines that gets you into trouble: "Oh yeah, I could give that a go."

For Chris Cairns it was a casual remark. For Fight for Life promoter Dean Lonergan, it was marketing gold. "When a name the size of Chris Cairns comes along and wants to fight, you take the opportunity and you grab it," says Lonergan.

So when Cairns, who played 62 cricket tests and 215 limited-overs internationals for New Zealand, told Lonergan he wouldn't mind trying boxing, he soon found himself matched against former Black Caps teammate Simon Doull in an intriguing all-cricket contest on December 14.

"I've always been a fan of boxing, but am I a fighter? Absolutely not," Cairns, 43, says. "Will I be shit-scared? Damn right. But it is one of those ‘oncers' - because I reckon there would not be a lonelier place in the world than in [the ring]."

Training has been a chance for Cairns to regain fitness: he says he was "truly overweight' and has dropped 15kg with the help of trainer Lee Parore, boxing coach Monty Betham and his own father, Lance. That's despite a travelling schedule which meant he only arrived back in New Zealand on Friday after a fortnight in Pakistan, where he's spending time trying to produce a reality TV cricket show.

Lonergan had no hesitation signing Cairns up to fight, but finding his opponent was trickier. Cairns suggested former Pakistan fast bowler Shoaib Akhtar or Australian cricketers Matthew Hayden and Andrew Symonds. Lonergan countered with Aussie rugby league international Sam Thaiday. "I told him I'm not that dumb," Cairns says.

Cairns, who moved back to Auckland earlier this year after a spell in Australia where his daughter Isobel was having cochlear-implant treatment for deafness, is working as a commentator for Sky and a columnist for the Star-Times.

Despite his pre-fight nerves, he's still cheerful, even if he wishes he'd kept his mouth shut when offering to "give it a go".

"It was one of those comments where you throw it out there - and then think can I grab it back? But it's too late."